Filter devices of this kind are known in the prior art. They are used, for example, in fuel systems for combustion engines to protect sensitive components, particularly injection systems, against impairment due to water fractions that are carried along in the fuel. The separation of the water fractions carried along in the fuel can be achieved by a coagulation process that causes the formation of water droplets on the filter medium. The water droplets can then flow off from a separating chamber formed on the filter element to the water collecting unit.